What causes disruptions of chromosome division in mammalian eggs?

A fundamental discovery of a medical problem affecting some women has been made by a team of Czech scientists. They are Dr. Michal Kubelka, Dr. Andrej Šušor and Dr. Martin Anger of the CAS Institute of Animal Physiology and Genetics and their foreign colleagues. They found the cause of aneuploidy in eggs that affects as many as 35 % of women over age 35. The missing or additional chromosomes in the egg can inter alia lead to the emergence of Down’s syndrome. The scientific team learned that the suppression of the function of the molecular pathway mTOR, which is responsible for the synthesis of specific proteins in the right place at the right time or its disruption, leads to genomic instability even though the egg is capable of being fertilized by sperm.